international telecommunications sattellite consortium (INTELSAT)
In 1964, an agreement on the provisional arrangements for a worldwide commercial satellite telecommunications system was signed by eleven governments. This agreement has been joined by over 100 telecommunications administrations and operating companies.
The objective is to establish and operate worldwide commercially operated telecommunications satellites, with Intelsat's responsibility limited to the space segment. The ground stations responsible for communications links are built and operated by the national operating companies.
The first Intelsat satellite, Early Bird, was positioned in the Atlantic segment in 1965. This was followed by Intelsat II with four satellites in 1967, Intelsat III with eight satellites in 1968, and six more Intelsat satellite systems with a total of about 40 satellites by 1996. All Intelsat satellites are GEO satellites positioned at an altitude of 36,000 km above the equatorial line. They are positioned over the world's oceans and provide international and intercontinental communications links. The satellites positioned over the Atlantic Ocean include the Atlantic Ocean Region( AOR), the one positioned over the Indian Ocean includes the Indian Ocean Region( IOR), and the one positioned over the Pacific Ocean includes the Pacific Ocean Region( POR).
The transmission capacity of the Intelsat systems has evolved dramatically: Whereas Early Bird had 240 long-distance channels, Intelsat iV already had 4,000 and Intelsat Vb 30,000. The satellites transmit the uplink in C-band at 6 GHz and the downlink at 4 GHz, as well as in Ku-band with the uplink at 14 GHz and the downlink at 11 GHz.